The present invention relates to fluid sample processors, particularly those used in combinatorial chemistry and DNA synthesis.
There are several multiple fluid sample processors known today, particularly those which are micro in size and are able to carry out from dozens to hundreds of experiments and analyses simultaneously. These devices, often called microfluidic devices, have particular use in combinatorial chemistry and DNA synthesis. These devices provide discovery and diagnostic tools which increase the speed and productivity of discovering new drug candidates and analyzing DNA materials, and do so on a miniaturized scale or platform that reduces cost and manual handling.
Many of the known devices utilize a plurality of layers, such as a feed-through layer, a fluidic delivery layer, and a well plate layer. A network of apertures and passageways in the various layers allow passage and transport of various materials and reagents to specific channels and wells for processing. Various mechanisms, such as electro-osmosis or pressure pumping precisely control the flow of materials in the processor.
These devices typically have a network or grid of openings and wells, arranged in rows and columns. Typically, materials added to the processor such as reagents are utilized to fill or couple with an entire row or an entire column of wells and reservoirs. This creates a problem where it is desired to address each well on an individual basis during, for example, DNA synthesis.
With pressure pumping on a microfluidic processor or chip, for example, the reagents are added to all of the wells in a single row or all of the wells in a single column, but it is not possible to individually add reagents separately to each well. There is a need, however, to spatially address each well for applications in oligonucleotide (DNA), peptide, and oligosaccharide synthesis, as well as biological assays. Single well addressability would also be useful in combinatorial libraries for drug discovery or catalyst optimization.
It is an object of the present invention to provide a new and improved multiple fluid sample processor, system and method, particularly for use in oligomeric synthesis including DNA, peptides, oligosaccharides and other repetitive chemical or biological processes. It is another object of the present invention to provide a system and method for individually addressing wells set up in a column and row format in a multiple fluid sample processor.
It is another object of the invention to provide a liquid handling diagnostic and analysis tool which increases the speed and productivity of synthesis, discovery of new drug candidates, primers or probes for genotyping, and antigen or epitope identification, and to do so on a miniaturized scale or platform that reduces cost and manual handling.
Other objects, purposes, and advantages of the present invention will become apparent in the following description of the invention, particularly when viewed in accordance with the attached drawings and appended claims.
In accordance with the present invention, a multiple fluid sample processor, system, and method are provided which utilizes a multi-layered fluidic array having micro-sized reservoirs, connecting micro channels and reaction cells and wells. Micro-sized wells typically range in sizes from 10 nl to 10 xcexcl and more particularly from 100 nl to 1 xcexcl. Micro-sized channels typically range in diameter from 10 microns to 5 millimeters and more particularly from 50 microns to 1 millimeter. A three-dimensional architecture of micro channels and micro-reaction vessels are constructed in the layers in order to transport reagents and other materials throughout the structure.
For a multi-layered device, the array preferably includes a top feed-through plate, a middle distribution plate, and a bottom well plate. The top feed-through plate serves as a cover for the array and contains micro-channels which direct materials to apertures selectively positioned above reservoirs located in the central distribution plate or layer. The apertures are in communication with micron-size reservoirs, micro channels, reservoir feeds, cell feeds, and overflow feeds, which are selectively formed in the center distribution plate. The channels and reservoirs form a delivery system where reservoirs are grouped into elongated columns and rows. In this manner, when a solution or materials is added to one of the apertures in the top plate, it is routed and distributed to fill all of the reservoirs or wells along a column or row in the distribution plate, which could be 6, 8, 10 or more reservoirs or wells. Then the materials in each reservoir or well in that column or row are all treated in the same manner and exposed to the same processing collectively.
Various fluid delivery mechanisms can be utilized to distribute the reactions and other fluids in the display array and to fill the appropriate reservoirs. These mechanisms include pressurized fluid delivery systems, electro-osmosis and electrohydrodynamic distribution.
The present invention provides a system for single well addressability when the chemistry employs, for example, a deprotection followed by a coupling step. Single well addressability is achieved by deprotecting a single column (row) of reaction wells and then coupling each row (column) of wells independently. After the coupling steps, the next column (row) is deprotected and then coupling the rows (columns) is performed. In this manner, each well can have a unique coupling event. Efficiency may be increased, of course, when different wells require the same coupling event. The system can be further optimized by organization of desired compounds to groupings requiring similar reagents.
In accordance with the present invention, when it is necessary or desired to address single reservoirs or wells individually, a particular column or row is deprotected and an appropriate material or reagent is added to a transverse row or column. Another transverse row adds another material to a second individual reservoir. By selectively deprotecting the rows and columns in this manner, each well or reservoir in the fluidic array can be addressed individually, allowing testing and analysis at each one separately.
The present invention can be utilized in any synthesis or analysis in which a chemical event takes place. Typically, these events include deprotection of a protecting group with an acid or base, but they could also include generally any activation event, such as oxidation, reduction or cell lysis followed by hybridization or antibody recognition.
With the present invention, miniaturized liquid handling systems are provided which perform the biological, chemical, and analytical processes fundamental to life sciences, research, and development. Hundreds of reactions can be performed in a microfluidic array device with each of the wells being able to provide a separate and distinct reaction and result. The present invention substantially reduces the time, effort, and expense required while improving the quality and quantity of the test results.
With the present invention, arrays of DNA can be synthesized on demand. The processor can be used for a high volume of sample processing and testing, as well as a search for new molecular targets and determining expression levels and response to known drugs. The processor can incorporate multiple assay formats, such as receptor binding, antibody-antigen interactions, DNA/RNA amplification and detection, as well as magnetic bead base separations. The versatility of the processor makes it available for use with synthesized work stations, genomic support stations, and analytical preparation systems.